Several Austrian economists including guys like Peter Schiff have used what is now called the circus analogy. It goes something like this.
A big traveling circus comes to a small town. All the circus people go have regular breakfast, lunch, and dinner at one of the town’s restaurants.
The owner of the restaurant is ecstatic. He get mountains of new businesses from the vast amount of circus folk eating at his restaurant. The problem is, he’s a moron. He assumes that all this new business is permanent and will never go away. He completely misinterprets the situation.